This core will support all the projects and will provide them with elastograms and sonograms of phantoms and tissues. This will be accomplished by utilizing specialized equipment constructed for this purpose. This equipment allows the acquisition of elastography data under a variety of conditions involving transducers, boundary conditions, applied stress and signal processing. Acquired images and data will be stored on Bernoulli disks and disseminated to the other projects. This core will also perform stress-strain measurements of phantom material produced in Core 9002 by Dr. Hall. Results of these measurements will provide the standard for comparison with elastography studies.